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Test Info: Warnings
- This test has a WPT meta file that expects 1 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /layout-instability/mousemove-becomes-drag.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<title>Layout Instability: no shift in mouse moves with a button pressed</title>
<style>
body { margin: 0; height: 2000px; }
#draggable {
top:50px;
left:50px;
width:50px;
height:50px;
background-color:blue;
position:absolute
}
</style>
<div id="draggable" ></div>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-actions.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="resources/util.js"></script>
<script>
const draggable = document.getElementById("draggable");
draggable.addEventListener('mousemove', function(event) {
// Move the element when the mouse moves.
draggable.style.top = event.pageY - 25 + 'px';
event.preventDefault();
}, false);
generateMouseMoveSequence = () => new test_driver.Actions()
.pointerMove(0, 0, {origin: draggable})
.pointerDown()
.pointerMove(0, 15, {origin: draggable})
.pause(100)
.pointerMove(0, 30, {origin: draggable})
.pause(100)
.pointerMove(0, 45, {origin: draggable})
.pause(100)
.pointerUp()
.pause(100);
promise_test(async () => {
const watcher = new ScoreWatcher;
// Wait for the initial render to complete.
await waitForAnimationFrames(2);
// Send pointer events for a sequence of mouse actions, mouse down, mouse moves and mouse up.
await generateMouseMoveSequence().send();
// Mouse moves which drag the objects should be counted as the excluding inputs
// for the layout shift.
assert_greater_than(watcher.score, 0);
assert_equals(watcher.scoreWithInputExclusion, 0);
}, "No layout shift when mouse moves with a button pressed.");
</script>